This invention relates to an improved method of making a tool mounting means for an agricultural implement, and more particularly to a method of making a torsion bar disk gang mounting assembly.
Current production torsion bar-type disk gang mounting assemblies, such as described in assignee's U.S. Pat. No. 3,706,345, include a plurality of disk gangs each suspended from a section of cylindrical tubular shaft. Adjacent shaft sections are coupled together by having their ends butted together inside of a cylindrical apertured coupling collar. The shaft ends are then held together by pins inserted through the collar apertures and through corresponding radial coupling bores in the shaft ends. The conventional method of constructing and assembling each gang section was to first drill the radial coupling bores through the shaft ends which were to be received by the collars. A radial torsion bar hole is then drilled through the shaft parallel to the coupling bores. One end of a torsion bar is then inserted into this hole and welded in place. The remaining parts, including two gang support arms and a rectangular tubular member, are then assembled onto the shaft so that the other end of the torsion bar is held between an L-shaped bracket on one support arm and an inner surface of the tubular member. Both gang support arms are then welded to respective ends of the tubular member. If not already, arms are positioned with their longitudinal axis angularly displaced 21.degree. from the axis of the coupling bores. With the gang support arms so positioned, a stop arm is welded to the shaft in a position in engagement with one of a pair of pivot stops rigidly mounted on the other gang support arm. In most cases, this process would result in an assembly in which the torsion bar was in an unloaded or unbiased condition. However, due to tolerances in the torsion bars and in other parts of the assembly, the torsion bars in some of the gang assemblies could be slightly preloaded or biased. When the plurality of disk gangs are then mounted on the disk frame with their shafts pinned together, the varying amounts of preload would cause different ones of the gang assemblies to hang at different heights. In order to produce a multiple gang assembly with uniform gang heights, it is then necessary to add shims to or build up by welding certain ones of the pivot stops. Still, due to this uneven preloading, it is not uncommon for this assembly process to produce a multiple gang disk assembly with as much as a 2-inch difference in ground penetration between different gangs.